It's an extreme example of a general problem: domestic flight attendants treating passengers like they are schoolteachers in charge of first-graders. Most flights I hear flight attendants scolding passengers over the PA system for daring to release their seatbelts while the plane is still taxiing or for making the decision to use the lavatory while the seatbelt sign is on. For some reason it has become ingrained in their culture that they are to be cops rather than serving men and women. It serves little purpose and makes the flight experience less enjoyable.